title: Highly enantioselective hydrogenation of styrenes directed by 2'-hydroxyl groups.
abstract: A new synthetic strategy that turns styrene-type olefins into excellent substrates for Rh-catalyzed asymmetric hydrogenation by installing a 2'-hydroxyl substituent is described. This methodology accommodates trisubstituted olefinic substrates in various E/Z mixtures, leading to valuable benzylic chiral compounds including (R)-tolterodine. It is also demonstrated that the 2'-hydroxyl groups could be readily removed in high yield without loss of ee from the products. Thus, this technology represents an attractive alternative to the Ir(P-N) catalyst system for the asymmetric hydrogenation of unfunctionalized olefins.
authors.affiliation: Chemical Process Research and Development, Amgen Inc., One Amgen Center Drive, Thousand Oaks, California 91320, United States. xiangw@amgen.com
authors.forename: Xiang
authors.initials: X
authors.lastname: Wang
authors.forename: Anil
authors.initials: A
authors.lastname: Guram
authors.forename: Seb
authors.initials: S
authors.lastname: Caille
authors.forename: Jack
authors.initials: J
authors.lastname: Hu
authors.forename: J P
authors.initials: JP
authors.lastname: Preston
authors.forename: Michael
authors.initials: M
authors.lastname: Ronk
authors.forename: Shawn
authors.initials: S
authors.lastname: Walker
mesh_terms: D006865:Hydrogenation; D017665:Hydroxyl Radical / Q000737:chemistry*; D015394:Molecular Structure; D013237:Stereoisomerism; D020058:Styrene / Q000737:chemistry*
chemical_list: D017665:Hydroxyl Radical; D020058:Styrene